Apple acknowledged Friday that some of its MacBook and MacBook Pro models have sticky keyboards, and will offer free repairs and refunds to anyone affected by the flaw.

The company said in a statement that the issue affects as "small percentage of keyboards" in certain MacBook and MacBook Pro models. Affected laptops may have keys that repeat letters, feel sluggish or don't respond at all.

Laptop owners can schedule repairs at Apple stores, send their laptops in to Apple repair centers or have the problem fixed by an authorized Apple repair service.

Apple customers have been complaining about these keyboards since the company introduced a new keyboard design three years ago. The "butterfly" design made keyboards thinner but quickly sparked complaints that the keys tended to stick or were unresponsive.

Apple faces three class-action lawsuits over what consumers have called faulty keyboards, but the company had not previously acknowledged the issue - or redesigned its laptops.

The following models are covered by the program:

MacBook (Retina, 12-inch, early 2015)

MacBook (Retina, 12-inch, early 2016)

MacBook (Retina, 12-inch, 2017)

MacBook Pro (13-inch, 2016, two Thunderbolt 3 ports)

MacBook Pro (13-inch, 2017, two Thunderbolt 3 ports)

MacBook Pro (13-inch, 2016, four Thunderbolt 3 ports)

MacBook Pro (13-inch, 2017, four Thunderbolt 3 ports)

MacBook Pro (15-inch, 2016)

MacBook Pro (15-inch, 2017)

Anyone affected by the issue who has already paid to have their keyboard fixed is eligible for a refund, Apple said.

Those considering taking advantage of the program should note some things in the fine print. If there's another problem with your laptop, Apple may have to fix that first and charge for unrelated repairs.

Also, don't dawdle: While there's no fixed end date for the program, Apple says that this covers computers for only four years after they're sold.

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